Twentieths to james a



(No Model.)

0. W. DUNCAN. GAR BRAKE No. 463,598. Patented Nov. 17, 1891.

14 1 12 ear-965',

7 UNITED STATES PAT NT OFFICE.

CIIARLES WARREN DUNCAN, on ST. LOUIS, MISSOURI, AssIGNo'R or ELEVEN-TWENTIETI-IS TO JAMES A. BAUMGARTNER, or SAME PLACE.

CAR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 463,598, dated November1'7, 1891. Application filed July 2, 1891. Serial No. 398,257. (Nomodel.)

To all whom it may concern:

Be it known that I, OHARLESWARREN DUN- CAN, a citizen of the UnitedStates, residing in the city of St. Louis and State of Missouri, haveinvented certain new and useful Improvements in Oar-Brakes, of which thefollowing is a full, clear, and exact description.

My invention relates to car-brakes adapted to be automatically operatedby air or steam pressure or by vacuum, more particularly tolocomotive-driver brakes adapted to be operated independently of or inconjunction with the train-brakes.

It has for its object the simplification and reduction of the number ofparts, and such a construction as to readily permit of the getting atand replacing of Worn parts and in an efficient and convenient means fora takenp when worn; and it consists in the novel features ofconstruction and in consequent operation in a car-brake hereinafterdescribed.

In the accompanying drawings, in which like letters of reference denotelike parts in the several figures, Figure l is a side elevation of myimproved brake as attached to a locomotive between two of the drivers.Fig. 2 is a view, as in Fig. 1, showing the method of disconnecting, asin replacing a brake-shoe; and Fig. 3 is a cross-section taken on theline 3 3 in Fig. 1.

I have illustrated only my brake and that part of the operativemechanism necessary to operate it. The brake, as a brake, can be,without modifying the essential features of my invention, operated bycompressed air or steam or by vacuum.

As illustrated, I operate my brake by compressed air admitted to theunder side of the brake-cylinder piston and regulated by any of thewell-known methods.

A represents the engine-frame, to which the brake-cylinder B and thedepending brakehangers O C are attached.

D and D are respectively the forward and rear drivers.

E is the piston-rod, to one end of which-is secured the piston F. To theother end of the piston-rod E are pivotally secured one end of the armsG and G, which are adapted to move about the pivot-joint on the end ofthe .tached arms G and G.

piston-rod E in a plane parallel to the plane of the drivers D and D. Tothe other ends of the arms G and G are pivot-ally and removably securedthe ends, respectively, of the adjustable connecting rod or spreader H,which is composed of two eyebolts with right and left hand threads,respectively, let into the correspondingly right and left threadedsleeve-coupling I. The connecting-rod H is designed to retain the arms Gand G in such. a position relatively that they form a wedgeshaped frameof the whole, resting, as shown in Fig. 1, in between thecorrespondingly-inclined surfaces of the brake-hangers O and G. Thecontiguous surfaces of the brake-hangers C and G and of the arms G and Gp are formed, respectively, with a tongue 0 and groove g, as indicatedin Figs. 2 and 3,10 prevent any lateral movement relatively. The lowerportion of the brake-hangers O and O are formed with alaterally-projecting portion. corresponding in form to the ordinarybrakehead, to which the brake-shoes K and K are removably secured by thebolts Ye.

M M represent the heads of the traversebolts or steady-rods connectingthe brakes on either side of the engine.

The principle of operation of myimproved brake is as follows: Pressureis admitted to the cylinder B below the piston F, which tends to raisethe piston-rod E, and with it the at- In this upward movement of thearms G and G, which are held apart by the connecting-rod II, theinclined surfaces thereof abut against the contiguous surfaces of thebrake-hangers O and O .forcing them apart against the drivers D and D,to the position as indicated in dotted lines in Fig. 1. WVhen thepressure is removed from beneath the piston F, the wedge-shaped frame,9c composed of the arms G and G and the connecting-rod H, will drop toits normal position and the brake-shoes K and K, secured to thebrake-hangers C and G, will fall away from the drivers D and D. hen itis desirable to replace a brake-shoe, as K, (see Fig. 2,) the removablebelt which connects that end of the connecting-rod to the brake-hanger O(which bolt is preferably secured by a springkey) is removed, and thenthe hanger Ioo can be dropped to a position away from the driver D tothe position, as shown in Fig. 2, convenient to remove the shoe K byremovin g the bolt 7c,which secures it to thehanger Among the principalfeatures of improvement in my new brake is in forming the usualbrake-head in the same piece with the brakehanger.

The advantages are these: The two-the brake-head and thebrake-hanger-being in one rigid piece and the brake-shoe being rigidlysecured to the same, the wear of the shoe will be dependent only on theposition of the pivot-point at which the brake-hanger is pivotallysecured to the engine-frame, about which it revolves as aeenter. Thispoint can be selected, so as to give the most uniform wear to the shoeand so as to wear the shoe most efieetually, thereby doing away with theusual uneven wear occasioned by the twisting movement given to the shoeby the turning of the drivers when the brake is applied to the wheels.

The object of making the connecting-rod II adjustable is in order to setthe arms G and G the proper distance apart to secure the most eifectualfriction between the brakeshoes and the contactsurfaces of the driverswhen the pressure is admitted to below the piston when the brakes areapplied-that is, for the defined amount of movement of piston-head. Thisadjustment is also to be used when the shoes are partially worn.

The special form of construction of the operative part of my brake-i. c,the part by which the brake is applied to the wheel-permits of theadjustment above referred to being made with one adjustment the turningof the right and left threaded sleevecoupling I.

I claim- I 1. In a car or locomotive brake, a brakehanger, incombination with a removable brake'slioe rigidly secured directlythereto, said brakehanger being formed with a laterally-proj ecting lugportion adapted to be fitted into a recess formed in the rear side ofthe brake-shoe, substantially as described, and for the purposesspecified.

2. In a carorlocomotive brake,brake-hangers dependently secured in asuitable position, said brake-hangers being formed with inclinedsurfaces, arms pivotally secured to the brake-cylinder rod, and aconnecting-rod retaining the said arms at an angle relative to eachother, combined and operating substantially as described, and for thepurposes specified.

3. In a car or locomotive brake, the brakecylinder piston-rod, incombination with arms pivotally secured to the projecting end of saidpiston-rod, a spreading-rod removably connected with the free ends ofsaid arms, retaining said arms at an angle relative to each other,brake-hangers dependently secured to the-supporting frame-work of thecar or locomotive, said hangers being formed with their adjacentsurfaces inclined corresponding to the angle at which the said arms areretained, combined as a whole and operating substantially as described,and for the purposes specified.

4. In a car or locomotive brake, the brakecylinder piston-rod, incombination with arms pivetall y secured to the projecting end of saidpiston-rod, an adjustable spreading-rod removably connected with thefree ends of said arms, retaining the said arms at an angle to eachother relatively,brake-hangers dependently secured to the supportingframe-work of the car or locomotive, said brake'hangers being formedwith an incline on their adjacent faees corresponding with the angle atwhich the arms are retained, the whole com bined and operatingsubstantially as described, and for the purposes specified.

5. In a car or locomotive brake, the brakecylinder piston-rod, incombination with arms pivotally secured to the projecting end of saidpiston-rod, an adjustable spreading-rod removably connected with thefree ends of said arms, retaining the said arms at an angle to eachother relatively, hanger-armsdependently and pivotally connected to thesupporting frame-work of the carer locomotive, said hangers being formedwith an incline on their adjacent faces corresponding approximately tothe angle at which the said arms are retained, the contiguous faces ofthe said arms and the said hangers being formed with a tongue andgroove, respectively, and brakeshoes removably secured to said hangers,substantially as described, and for the purposes specified.

In testimony whereof I ai'lix my signature, in presence of twowitnesses, this Grh day of June, 1801.

CHARLES \VARREN DUNCAN.

Witnesses;

J. W. CROOKES, A. RAMEL.

